Sign



Aug. 23, 1932- R. EBARCLAY 1,873,261

' SIGN Filed Sept). 16. 19.50

Patented Aug. 23, Y 1932 UNITED STATES PATENT `onu-iclai* ROBERT E BABCLAY, OF CHICAGO, ILLINOIS-'ASSIGNOB T0 FEDERAL ELECTRIC PANY, 0Fl CBIGAGO, ILLINOIS, A O0R POBATION 0F NEW 'I OBK 'sicn Application mea 'september 1e, mo.' serial no. 482.240.

My invention relates to luminous devices.

In its broader aspect my invention comprises means adapted to be associated with a source of light for not only augmenting 5 and boosting-up the lighting eiect,'but also fordispersing and refracting the light rays to provide a more uniform glow or lighting eifect.

The invention is adaptable to various types 10. of luminous devices', including lighting devices, display devices, and includin also signs and the like, and the general object of my invention in such adaptations is to provide uniform diffusion and increased brill'5 liance of the lighting eifect.

In the general adaptations of my invention, it includes a device or .devices adapted to be associated with a light source, and includes translucent light-refracting and light- 20 augmenting means whereby the device or devices will be illuminated with uniform maximum intensity notonlyby the light rays passing directly from the source oflight, but such illumination will be in turn augmented and 2" intensified by rays of light from extraneous sources.

For purposes of illustration and not by way of limitation, the invention is herein n Sillustrated as applied particularly to a dis- "3 play device such as a luminous; sign, wherein the luminous element comprises an illuminated bulb in the form of a tube enclosing a column of gas electrically excited so as to glow and produce a source of light. This type of tube is popularly known as a neon tube.

Many of the inherent advantages of my invention are clearly illustrated by an exposition of its adaptation to a display sign of a neon tube type. In this type of sign heretofore made Aand prior to my invention,l the thickness of the glass tube on either side of the. enclosed column of excited, luminous gas 4, was quite perceptible, and in a measure ded tracted from the appearance of the sign, and

.or joining, of` two sections of tubin without there'were numerous other deficiencies in 4these signs hereinafter brought out which my present invention overcomes.

One of the objects of my invention is to provide a gas-filled luminous device wherein means is provided for au inenting and for `refracting or dispersing te lighting e'ect of the luminous gas in such a manner as to cause a uniform glow of unusual brilliance.

One of the objects of my invention resides 1n providing a luminous device so constructed that light rays of quite feeble intensity will cause the practical illumination of the device so that even in dark places it will glow and attract attention.

Another object of my invention, particularly in its adaptation to the gas-filled luminous tube type of display device, is to' provide means for augmenting and refracting or dispersing the light from a luminous column of gas in such a manner as to veliminate the heretoforeI objectionable appearance and presence of the glass wall on either side of and enclosing this central column..

Another object in connection with the adaptation of my invention to so-called neon tube display signs is to permit the utilization of glass tubes of smaller diameter, while maintainin practically the equivalent lightil'ig e'ect as ormerly produced by tubes of larger diameter, and whereby, as a result of the use 'of the tubes of smaller diameter, sharper bends in the glass tubes may be utilized in the formation of indicia or characters of the display device. 30

Another object of my invention as adapted -to so-called neon tube display signs 4resides/in the production of such a tube construction which permits the welding, sealing Ithel formation of.' unsightly bad joints or glass junctions. l

Yet another object Vof my invention, both in its broader aspects and in its adaptation to neon'tube devices, resides in the provision of means for producing a practical and efiicient li hting eii'ect in the daytime as well as at nig t-time.

Yet another object of my invention, both in its broad aspects and in its adaptation .to so-called neon tube constructions, resides in the provision of means for producing colored effects more eiciently and economi- Yyet another object of my invention, as particularly applied to so-called neon' tube Adisplay devices, resides in the` provislon of means for practically eliminating the presence of so-called paint-outs.

These and other objects of my invention will be apparent from the perusal of the following specification, when taken in connection with ythe accompanying drawing, wherein: l

Figure 1 shows one of the adaptations of my present invention, to-wit, my invention as applied to a display device such as a si of so-called neon tube type, showing t e glass tube as provided .with a coating of luminescent material;

Figure 2 is a cross-sectional view of the glass tube shown in Figure l, showing-the exterior coating of luminescent material;

Figure 3 is a perspective view of one end of a modified form ofmy invention as applied to a so-called neon tube display device; and

Figure 4 is a cross-sectional .view of a modiiied form of tube illustrated in Figure 3.

' Referring to my invention in detail, I have ound that by "coating a transparent carrier such as glass, with a translucent, luminescent medium such as fluorescent or phosphorescent material or a combination of said materials, that light rays, in passing through said medium or if projected upon said medium, will be considerably augmented and will be refracted and dispersed so as to cause the medium to glow in a uniform manner with marked brilliance. I have found, for instance, in the adaptation of my invention to lighting devices where the source of light is enclosed within a. glass shell or tube, that if the shell or tube be coated with a translucent, luminescent medium, the source of light therewithin will cause a uniformly diffused glow or effulgence throughout the entire coating, due to the refractive or dispersive character of the coating, and in addition the lighting effect will be greater, due to its luminescent characteristics. vIn addition, the lighting due to the internal source of light will be enhanced or increased by any extraneous rays of light which may be present. I have also found that in the utilization of color effects the luminescent coating of selected or desired color is greatly enhanced by the refractive characteristic of the coating. It is to be clearly understood that these characteristics of my invention are not restricted to so-called neon tube devices, but are of more general ap lication. 4

Inasmuch as have selected a gas-filled, luminous tube display device as a means for illustrating my invention, I desire to point out its advantages in connection therewith. Prior to my invention, these luminous gas- .filled tubes had been objectionable in the fact that the luminous column of gas appeared as quite distinct from the relatively thick glass walls ofthe tube, and the lighting effect was Vmore or less confined` by the central part of the glass tube. Various attempts `have been made to eliminate' this disadvantage, but with.

out practical success. In some instances attempts have been made toy utilize frosted tubes, but they have tended to deteriorate,

crack, and make black marks'. So also in the use of frosted tubes, where it has been necessary to weld or join one tube section to another, it has been found that the-frosted tubes make very bad joints, which seriously interfere` with the commercial appearance and sale of such tubes. Initlie use of the former types of tubes, it has been necessary to utilize glass tubing of a predetermined maximum diameter in order to produce a practical and suiiicient lighting eilect from the central luminous column of gas, and these glass tubes of larger diameter have practically precluded the utilization of sharp bends in the glass because of tendency tov ydispersive and luminescent eifect upon the light rays, so that, as a result of the refractive l and dispersive characteristics of [the coating, the entire tube glows with a uniform effulgence or lighting effect so that the heretofore objectionable appearance of the glass walls is eliminated. In addition to this unusual dispersive or refractive power of the coating, it also possesses the beneficia-l characteristic of boosting up, augmenting or increasing the lighting effect of the internal column of excited gas, so that increased brilliance is produced.

By the term luminescent coating I mean a coating of any material which, when exposed to the influence of light, has or develops the power of emitting luminescence which has no connection with ordinary thermoradiation. This power of luminescence is of two types: fluorescence and phosphorescence.

In fluorescence the luminescence is only visible during the period of excitation and vanishes the insta-nt the excitation ceases, while in phosphorescence the luminescence continues for a measurable time after the excitation has ceased. In the case of phosphorescence the persistence, or period of time during which the luminescence persists after the excitation ceases, varies enormously with dierent substances, all of which are well known in the art. f

I prefer the coating of fluorescent material,v

escent coating on a plain glass tube, I haveV found that this coatlng, when exposed to a light such as the central column of excited gas, excites the coating in such a way that the coating itself gives of light and disperses the light in such a manner that the light given off by the tube will bev greater than the light which is emitted by the central column of excited gas itself, and this coating will so disperse or refract the light that the glow will be practically uniformly co-extensive throughout the entire length and diameter of the glass tube. By .the utlllzation of these translucent, fluorescent or phosphory escent coatings on the glass tubing, dii'erent color e'ects may be easily obtainable.-

In accordance with another aspect of my invention, I may accomplish further objects of my general invention, by providing the glass tube itself with a plurality of lightrefracting and dispersing elements which, within the contemplation of the broader features of my invention, may be incorporated as an integral part of the glass itself, or may be adhered to the surface of the glass by suitable adherents such as, for instance, a varnish, or by a translucent coating and particularly a luminescent coating previously mentioned, to wit, a fluorescent or phosphorescent coating. As a practical exemplification ofa tube constructed with a plurality of relatively fsmall refractive and dispersive elements, I

haveshown in Figure 3 of the drawing my improved form of tube wherein the usual glass tube 2 is provided with an externall coating of relatively small or minute lightrefracting elements such as beads, prisms or other small bodies capable of refracting light. In the selected embodiment of my invention I have'used small glass beads. These glass beads may be adhered thereto by means of\ any type of suitable varnish, or by means of other adherents, but I prefer to utilize the translucent, fluorescent or phos horescent coatlng heretofore described. ese 'gla beads may be vformed round, square or as 4small glass prisms. In fact,- they may be of any s hape and material which will produce the rlght refractive and dispersive effect described herein. In some instances I may use small globules of varnish or the like suitably glass for effecting the light vfracting substances 4 such as, for instance, 'the fluorescent or phosphorescent coating hereinbefore described.

In Figures 3 and 4 of the drawing I have shown the modification wherein the relatively small light-refracting elements in the form -of glass beads are applied as a coating to the tube on account of eing adhered thereto,

preferably by a coating of a luminescent material. p

From the foregoing description it will be Vseen that the display device constructed in accordance with my invention possesses many advantages over` similar devices heretofore known in that the luminescent and light-re fracting coating gives maximum brilliance to the light, gives uniformity of glow, and distributes all the light over the entire surface of the coating, eliminates the heretofore objectionable presence of the glass wall, en-

hances'the color effect of the light, and pro- 393 vides a light which is usable in night-time and in daytime, and also in relatively dark places.

For instance, in quite a dark room a display device of this character will shine with marked luminosity even when feeble light rays are projected upon it. This is apparently due to the fact that the luminescent characteristicof the coating will boost-up these light rays, and the light-refracting characteristic of the coating will disperse the light and render the luminous eect uniform. In addition, the refractive, translucent lightrefracting elements, when used, will increase the coloring efect of the colored luminescent material,and this lighting e'ect is rendered uniform due to the fact that these minute refracting elements diifuse and disperse the light and pass the light rays from one to the other. Thisv is particularly noticeable where the source of light approaches the device from the side, and in such circumstances' a uniform lighting effect is obtained as distinguished from conventional devices, wherein a dark effect-Will be very noticeable toward the portion of the sign remote from the source of light. y

In the adaptation of the broader aspects IGS of my invention to the gas-filled and other tice, and due to this augmented illumination of the luminescent coating, I am enabled to use glass tubes of smaller diameter than heretofore used in signs and other ,devices for producing illumination of equivalent intensity as compared with tubes of a larger diameter. Furthermore, by being able to use glass tubes of smaller diameter, I am likewise enabled to produce sharper bends or turns in the glass tube than has heretofore been possible with the larger diameter tubes.

Another advantage apparent from the utilization of the luminescent coatings such as fluorescent or phosphorescent coatings resides in the ability cheaply and easily to manufacture tubes of various colors and capable of giving lighting effects of maximum efficiency.

It will also be apparenti that in the construction of signs land tubes in accordance with my invention, the tube may be coated and/or provided with the glass bead surface' after it is made and bent to form.

Still another advantage resides in the fact that in the utilization of such a tube or a black background, the luminescent coating, particularly when provided lwith the small beads, will shine out with maximum illuminative efficiency in the daylight, andfurther- `more will stand out prominently against. the

background, and will thereby render less prominent the black portions or paint-outs of the glass tube.

Another important advantage of my invention resides in the characteristics of the relatively small light-refractive elements, to wit, the glass beads. These elements are adapted', as set forth above, to refract or disperse light rays from the light source within the tube, namely, the exclted gas, thereby intensifying the glow 0f the sign when used at night. In addition to this function, said light-refractive members serve, when the sign is used in the daytime, to pick up and refract or disperse light rays received thereby from either the natural outdoor light or from some artificial source, thereby to render the sign more attractive to the eye of an observer. These beads being composed of transparent or semi-transparent material adhered to the glass tube, by a coating of luminescent material, as above set forth, the beads will serve, when a light ray is directed thereagainst from an external source, to intensify the glowing of the colors of the coating. Obviously the use of transparent beads represents only one form of the invention, as said beads may also be made of translucent colored material so as to bring about the desired intensifying effect.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent-is:

1. A luminous device comprising a glass tube enclosing a column of gas adapted to be electrically excited to be luminous, said tube having adhered to its external surfaces by means of a luminescent cement, a plurality of relatively small glass beads providing light-dispersing surfaces in order to overcome the visual effect produced by the thickness of the tube walls.

2. A luminous device comprising a glass tube enclosing a column of gas adapted to be electrically excited to be luminous, said glass ltube being coated with a plurality of relatively small light-refracting elements adhered thereto `by luminescent material.

3. A luminous device comprising a glass tube enclosing a column of gas adapted to be electrically excited to be luminous, said glass tube being coated with' a' plurality vof relatively small glass beads adhered thereto by luminescent material.

4. A sign comprising a substantially black background and including a glass tube mounted thereon, said tube being filled with a gas adapted to be luminous by electrical excitation, said glass tube carrying a plurality of relatively small glass beads adhered thereto by a coating of luminescent material of a color substantially distinct from the black background of the sign.

5. A display device including a transparent supporting member carrying a coating of relatively small translucent light refracting elements adhered thereto by translucent luminescent material.

6. A display device comprising means forming a panel, a glass tube, containing a column of gas adapted to be electrically excited to be luminous, supported in front of the panel in spaced relationship therewith, the surface of the glass tube, facing away from the panel, comprising a luminescent light refractive layer whereby when the gas in the tube is excited, said luminescent layer will be activated toV create a surface glow on the tube in such a way as to hide the visual effect normally imparted in uncoated tubes of the class described by reason of the thlioclmess of the glass in the walls of the tu e.

7. A display device as set forth in claim 6 wherein the luminescent layer, with which the tube iscoated, comprises relatively small light-refracting elements and a luminescent material mounted on the surface of the tube.

8. A display device as set forth in claim be electrically excited to create luminescence therein, a surface, at least, of the glass tube facing in the direction from which the tube is viewed, being provided lwith a luminescent layer comprising light-refracting vparticles of glass fastened to the surface of the tube by a, luminescent binder.

10. A luminous device comprising a glass tube containing a column of gas adapted to be electrically excited to create a luminescence therein, a surface, at lea-st, of the glass tube facing in the `direction from which the tube is viewed, being yprovided with a luminescent layer comprising relatively smallv light-refracting particles fastened to the surface of the tube by means of a luminescent binder.

11. A luminous deviceas set forth in claim 10 wherein the light refracting particles are made of glass. l*

In Witness whereof, I have hereunto subscribed my name.

ROBERT E. BARCLAY. p 

